Bitcoin vs. Quantum Computing: Imminent Threat or Overblown FUD?

The idea that quantum computing could one day break Bitcoin resurfaced on X after , , and several on-chain analysts. While the topic sounds alarming, most experts agree this is a long-term engineering challenge, not an imminent existential risk.

A few days ago, Michael Saylor publicly supported post-quantum cryptography upgrades for Bitcoin. He views this emerging technology not as a death blow, but as a challenge that will force the network to become stronger in the long run.

Wu Blockchain neatly explained what could happen, saying that if Bitcoin upgrades to quantum-proof security, active owners could move their funds to safe new addresses. However, the estimated 20 to 25% of all Bitcoin already lost or forgotten would be stuck forever, which would make Bitcoin effectively rarer over time by shrinking the amount that can actually be traded.

“Bitcoin does not use encryption. Get your basics right.”

Bitcoin relies on ECDSA and Schnorr signatures, which could theoretically be broken by Shor’s algorithm if a sufficiently powerful, fault-tolerant quantum computer existed.

Interestingly, Taproot’s (Bitcoin’s upgrade) usage has fallen sharply, driven by growing worry about future quantum computers. Taproot was introduced in 2021 and reveals public keys immediately on-chain due to Schnorr signatures, which could make those specific BTCs more at risk if advanced quantum computers are ever developed.

For instance, SegWit v0 addresses keep public keys hidden until coins are spent, offering temporary protection even in a quantum future.

Adam Back and most leading Bitcoin developers are unanimous in that we are decades away, not a few years.

“The risks are short term NIL. This whole thing is decades away, it’s ridiculously early and they have massive R&D issues in every vector of the required applied physics research to even find out if it’s possible at a useful scale.”

Current estimates place a quantum computer capable of breaking Bitcoin’s cryptography 10 to 30 years away, assuming no unforeseen breakthroughs and no boosts to Bitcoin’s network take place.

Back mentioned current work on quantum-resistant security options for Bitcoin, emphasizing the need to be ready rather than to panic. The likely future path is that Bitcoin will introduce optional quantum-resistant address types.

Users would then also be able to move their funds to these addresses over long periods of time. What’s more, this could be done without a sudden network split or an emergency drop.